There is a recent topic on the MacFixit site that mentions problems with running Classic under 10.3.9.
Apparently this can be resolved by turning off the Apple Menu Options extension in Classic.
Check the MacFixit site for more info: http://www.macfixit.com/

[quote="GeoffRoynon"]
Apparently this can be resolved by turning off the Apple Menu Options extension in Classic.

Thanks for the hint. Tried it. It works only for 2-3 starts of Nisus for me, then the same problem occurs. Tried also to minimize the system extensions in Classic, but also without success. I think I have to wait for a Bugfix from Apple.

I started having the same problem as yourself with Nisus getting part-way through its initialisation and then simply vanishing with no error messages.
I looked in the MacOS9 System Folder and found a Clipboard file which was 12K in size - this file should be zero size apparently (someone reported this on the Nisus list some time ago as causing problems). I stopped Classic, removed the Clipboard file, and restarted Classic and Nisus is running fine now. Don't know if it was the Clipboard or stopping and starting Classic.
You could check your System Folder and see if you have a Clipboard file and remove it - see if it helps.

after a lot of trials the problem vanished for me too. But I can't say what the solution was. I switched of a lot of control panels and system extensions, so that it is still enough for Nisus and ATM. Made also what you mentioned from macfixit and <http://discussions.info.apple.com/webx? ... 9.68ac60e2>. Finally used the command "Repair MacOS 9 permissions" from the harddisc utility. And now Nisus starts again.